Clutches & Brakes — validation & limitations

What this calculator checks and the method behind each result, the independent reference cases its engine is tested against, and what it does not check. Use it to decide how far you can rely on a result.

Open the Clutches & Brakes

What it calculates

Standard / method: Shigley's Mechanical Engineering Design

Shigley §16 — uniform-wear and uniform-pressure disc models, worn-in (uniform-wear) cone model, drum shoe model; capstan equation (e^μθ) for band brakes; engagement energy and thermal rise per engagement.

Torque capacity and safety factor for single-disc, multi-disc, cone, drum and band-brake clutch types
Uniform-wear and uniform-pressure models for disc clutches; worn-in (uniform-wear) capacity for cone clutches
Capstan equation (e^μθ) for self-energising and de-energising band brakes with tight/slack-side force output
Peak contact-pressure check against the lining material allowable
Thermal rise per engagement — slip power, heat energy and estimated disc temperature rise
Engagement dynamics panel — synchronisation speed, heat per engagement and engagements-per-hour thermal limit

Validation evidence — independent reference cases (0)

Each case runs the tool's engine on a worked example whose values come from a published source or a hand derivation from the cited equations, and an automated regression test asserts the engine against those values within the stated tolerance. "Conservative" means the engine is known to sit on the safe side of the reference and the test asserts that side. Sources are cited; their text is not reproduced.

No independent reference case is registered for this tool yet. Its engine is covered by the regression suite, but no published worked example has been reproduced end to end.

Limitations

Not checked by this tool

Heat build-up over repeated engagements against the real cooling — The temperature rise is for one engagement; check the duty against the lining maker's thermal capacity
Actuation: spring, piston or lever force and its loss with wear — The required clamping force is reported; size the springs with /springs or the actuator with its maker
Spline / hub connection of the plates and the shaft-hub joint — Check spline flank pressure with the maker's data (or the /keys spline panel) and the hub with /keys
Engagement dynamics: slip time and torque peak at lock-up — Engagement time is an input; derive it from the inertias and slip torque or take it from the maker
Drag torque and churning losses when disengaged (wet multi-disc) — Not modelled; use the maker's drag-torque data
Thrust bearing for the axial clamping force — Size it with /bearings
Band brake: band/strap tensile and anchor-pin strength — Only the lining pressure is checked; size the band section and the anchor pin for the tight-side tension F1 with the maker's data

Results are engineering calculations for qualified users — see the disclaimer. Other tools: all validation pages · standards reference · symbols glossary.